u-boot/drivers/clk/altera/clk-mem-n5x.c
Siew Chin Lim 14b7fba31f drivers: clk: Add memory clock driver for Intel N5X device
Add memory clock manager driver for N5X. Provides memory clock
initialization and enable functions.

Signed-off-by: Siew Chin Lim <elly.siew.chin.lim@intel.com>
2021-08-25 12:55:13 +08:00

136 lines
3.3 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2020-2021 Intel Corporation <www.intel.com>
*/
#include <common.h>
#include <asm/arch/clock_manager.h>
#include <asm/global_data.h>
#include <asm/io.h>
#include "clk-mem-n5x.h"
#include <clk-uclass.h>
#include <dm.h>
#include <dm/lists.h>
#include <dm/util.h>
#include <dt-bindings/clock/n5x-clock.h>
DECLARE_GLOBAL_DATA_PTR;
struct socfpga_mem_clk_plat {
void __iomem *regs;
};
void clk_mem_wait_for_lock(struct socfpga_mem_clk_plat *plat, u32 mask)
{
u32 inter_val;
u32 retry = 0;
do {
inter_val = CM_REG_READL(plat, MEMCLKMGR_STAT) & mask;
/* Wait for stable lock */
if (inter_val == mask)
retry++;
else
retry = 0;
if (retry >= 10)
return;
} while (1);
}
/*
* function to write the bypass register which requires a poll of the
* busy bit
*/
void clk_mem_write_bypass_mempll(struct socfpga_mem_clk_plat *plat, u32 val)
{
CM_REG_WRITEL(plat, val, MEMCLKMGR_MEMPLL_BYPASS);
}
/*
* Setup clocks while making no assumptions about previous state of the clocks.
*/
static void clk_mem_basic_init(struct udevice *dev,
const struct cm_config * const cfg)
{
struct socfpga_mem_clk_plat *plat = dev_get_plat(dev);
if (!cfg)
return;
/* Put PLLs in bypass */
clk_mem_write_bypass_mempll(plat, MEMCLKMGR_BYPASS_MEMPLL_ALL);
/* Put PLLs in Reset */
CM_REG_SETBITS(plat, MEMCLKMGR_MEMPLL_PLLCTRL,
MEMCLKMGR_PLLCTRL_BYPASS_MASK);
/* setup mem PLL */
CM_REG_WRITEL(plat, cfg->mem_memdiv, MEMCLKMGR_MEMPLL_MEMDIV);
CM_REG_WRITEL(plat, cfg->mem_pllglob, MEMCLKMGR_MEMPLL_PLLGLOB);
CM_REG_WRITEL(plat, cfg->mem_plldiv, MEMCLKMGR_MEMPLL_PLLDIV);
CM_REG_WRITEL(plat, cfg->mem_plloutdiv, MEMCLKMGR_MEMPLL_PLLOUTDIV);
/* Take PLL out of reset and power up */
CM_REG_CLRBITS(plat, MEMCLKMGR_MEMPLL_PLLCTRL,
MEMCLKMGR_PLLCTRL_BYPASS_MASK);
}
static int socfpga_mem_clk_enable(struct clk *clk)
{
const struct cm_config *cm_default_cfg = cm_get_default_config();
struct socfpga_mem_clk_plat *plat = dev_get_plat(clk->dev);
clk_mem_basic_init(clk->dev, cm_default_cfg);
clk_mem_wait_for_lock(plat, MEMCLKMGR_STAT_ALLPLL_LOCKED_MASK);
CM_REG_WRITEL(plat, CM_REG_READL(plat, MEMCLKMGR_MEMPLL_PLLGLOB) |
MEMCLKMGR_PLLGLOB_CLR_LOSTLOCK_BYPASS_MASK,
MEMCLKMGR_MEMPLL_PLLGLOB);
/* Take all PLLs out of bypass */
clk_mem_write_bypass_mempll(plat, 0);
/* Clear the loss of lock bits (write 1 to clear) */
CM_REG_CLRBITS(plat, MEMCLKMGR_INTRCLR,
MEMCLKMGR_INTER_MEMPLLLOST_MASK);
/* Take all ping pong counters out of reset */
CM_REG_CLRBITS(plat, MEMCLKMGR_MEMPLL_EXTCNTRST,
MEMCLKMGR_EXTCNTRST_ALLCNTRST);
return 0;
}
static int socfpga_mem_clk_of_to_plat(struct udevice *dev)
{
struct socfpga_mem_clk_plat *plat = dev_get_plat(dev);
fdt_addr_t addr;
addr = devfdt_get_addr(dev);
if (addr == FDT_ADDR_T_NONE)
return -EINVAL;
plat->regs = (void __iomem *)addr;
return 0;
}
static struct clk_ops socfpga_mem_clk_ops = {
.enable = socfpga_mem_clk_enable
};
static const struct udevice_id socfpga_mem_clk_match[] = {
{ .compatible = "intel,n5x-mem-clkmgr" },
{}
};
U_BOOT_DRIVER(socfpga_n5x_mem_clk) = {
.name = "mem-clk-n5x",
.id = UCLASS_CLK,
.of_match = socfpga_mem_clk_match,
.ops = &socfpga_mem_clk_ops,
.of_to_plat = socfpga_mem_clk_of_to_plat,
.plat_auto = sizeof(struct socfpga_mem_clk_plat),
};